You may need to find out OS PID from sid in Oracle to check the performance related to OS and Database. In Linux every process has it’s process ID – PID and a user can easily identify PID from SID.
Query to check OS PID from SID in Oracle.
Set lines 200 col sid format 99999 col username format a15 col osuser format a15 select a.sid, a.serial#,a.username, a.osuser, b.spid from v$session a, v$process b where a.paddr= b.addr and a.sid='&sid' order by a.sid;